Tilter mechanisms for slatted blinds have in the past utilized a worm gear in meshing engagement with a worm wheel to provide for the transfer of forces necessary to tilt the slats of a venetian blind assembly. It has been customary in such mechanisms to have the toothed worm wheel connected to a tilt bar which in turn tilts the slats while the worm gear is connected to an operating member such as a wand. Upon rotation of the wand by an operator, forces are transmitted from the wand via the worm gear to rotate the worm wheel and consequently the tilt bar which in turn tilts the slats.
In order to prevent jamming of the mechanism when the slats have been tilted to their full degree or limit of tilt to a closed position as might occur if forces are continued to be applied to the wand, the worm wheel in such prior mechanisms has had a blank portion on its periphery which is void of any teeth. The result is that when the slats reach their limit of tilt, the blank portion will be opposite the teeth of the worm gear such that there is disengagement of the worm gear with respect to the worm wheel so that no further force may be applied to the worm wheel which might result in jamming or binding and resultant damage to the mechanism. This provision of having a blank untoothed portion in the toothed worm wheel has not proved entirely satisfactory since, in many instances, the worm gear will not reengage and mesh with the teeth of the worm wheel when the slats are to be tilted to a partially open or fully open position from the fully closed position.
It is therefore an object of my invention to provide for a tilter mechanism which will insure that only predetermined forces may be applied to the tilter mechanism at the limit of rotation or tilt of the slats in order to prevent binding or jamming of the mechanism.
It is a further object of my invention to provide for a tilt mechanism which has a worm gear and a toothed worm wheel which will reengage and mesh together upon application of forces to tilt the slats from the fully tilted and closed position to a partially open or fully open position.